Printing telegraph exchange system



Aug.9,1932. A. JIPFA'ET AL 1,870,997v

PRINTING TELEGRAPH EXCHANGE SYSTEM Filed Jan. 4, 1950 4 Sheets-Sheet 1Aug. 9, 1932. A, PP ET AL x 1,870,997

PRINTING TELEGRAPH EXCHANGE SYSTEM Filed Jan. 4, 1930 4 Sheets-Sheet 2 u'l W v .um l I ALJ-Snug:

Aug. 9, 1932. A. .uPP ET Al.

PRINTING TELEGRAPH EXCHANGE SYSTEM 4 sheets-sneu 5 y Filed Jan. 4, 1950Aug. 9, 1932. A. JIPP ET Al.

PRINTING TELEGRAPH EXCHANGE SYSTEM 4 Sheets-Sheet 4 A Filed Jan. 4. 1930MMN @MW mmm.

Patented Aug. 9, 1932 UNITED STATES' AUGUST J' IPP, OF BERLIN-SPANDAU;E-H'RHARD ROSSBERG, OF BERLIN -SIEME-NSSTADT;

PATENT FRANZ SIMON AND .ALFRED SCHEUNERT, OF BERLIN-CHARLOTTENBURG, ANDWILLY SKAWRAN, OF BERLIN-NIEDERSCHONHAUSEN, GERMANY, ASSIGNORS T0SIEMENS tv HALSKE, AKTIENGESELLSCHAFT, OF SIEMENSSTADT, NEAR BERLIN,GERMANY, A CORPORATION OF GERMANY PRINTING TELEGRAPH EXCHANGE SYSTEMApplication led January'4', 1930, Serial No. 418,460, and in GermanyDecember 28, 1928.

Our invention relates to improvements in systems of communication, andmore particularly tele-printers, tele-writers and the like.

It is well known in the art to design communication systems fortele-printers, telewriters and the like in such a manner that theapparatus is always ready to receive a message and the transmitted signsare automatically printed or recorded by the receiving apparatus.Neither for switching the receiving apparatus on or off nor duiing the'transmission of the messages is any attendant required at the receiving`end.

It is, however, a drawback that .in particular in extensive systenis'andsuch for automatic connection the calling subscriber has no means at hisdisposal of ascertaining at once whether the correct conii-ection hasbeen made and that the receiving apparatus is really ready to receivethe message. This uncertainty is particularly disagreeable if a Ymessage is to be kept secret or is of great importance.

The object of our invention is to provide an automatically operatingreturn signaling device or indicator which becomes operative when a callis received and transmits a Signal to the calling subscriber. This mayin the simplest case consist of a. signal indicating readiness, butpreferably a special signal identifying the called up subscriber will betransmitted, for instance, his name. The return signaling device is inits mode of operation preferably adapted tothe tele-printer so that thereturn signal can be written down by the receiving apparatus of thecalling subscriber. l

An impulse transmitter of suitable construction is therefore employed,such as a transmitter for standard perforated paper tapes, or astep-by-step mechanism of the nature of dial selectors, or a contactmechanism with cam control.

` Preferably the return signaling device is connected with a contact ofthe receiving relay in such a manner that said device is released by therelay as soon as the calling impulse arrives. The receiving relay ispreferably connected in such a way that its armature is operated once bythe calling imdcpresses` a calling key 'whereupon at the' called stationthe armature ofthe receiving relay is reversed and the return signalingde vice or recorder rendered operative. It will be understood thatinstead of the key other means may be provided which start the returncalling device automatically after the through connection has lbeeneffected.

The return report is now Written down by the receiving apparatus of thecalling subscriber so lthat this subscriber knows that he is correctlyconnected and that the station called up is ready to receive hismessage. The return signaling device is then automatically renderedinoperative again and switches in the receiving apparatus at the calledstation if this should not already have been done by the callingimpulse. No attendants whatever are thus needed at the called station.

During .the transmission of messages whichl then begins the returnsignaling device remains inoperative and is made ready for service againonly when the connection lis interrupted. On the other hand it might bedesired that the return signaling device should -not start at all when amessage is sent out, i. e. at the calling' station. Switching means aretherefore provided which are indirectly or directly rendered operativeby the subscriber prior to or when Certain difficulties arise, however,in me-- -orifice chanically operating apparatus working withoutrevolving distributor brushes, as for instance the mechanical apparatusoperating on the start-stop principle. In this appara- 5 tus thecombination of current impulses (as a rule iive impulses) correspondingto the signal or symbol to be transmitted at the time is set in such amanner that Contact.

springs which are controlled by a controller shaft and which can beclosed consecutively during each revolution of the control shaft, arepartly locked in a mechanical manner by key-operated levers.

In one embodiment of our invention these contacts are electricallyconnected with the signal transmitter serving ,for return signaling. Thearrangement is preferably such that during the return signaling the runof the control shaft depends upon the operation of the signaltransmitter in such a manner ythat the signal transmitter controls themechanism which releases the control shaft for one revolution at a time.

In the circuits of the contacts controlled by the controller shaftareincluded the contacts of the signal transmitter, for instance thecontact arms andcontacts of a dial selector of known design, the bank ofcontacts of which is wired in accordance with the return symbol or sinal. Instead of a dial 0 ates, for instance, in such a manner that thereceiving relaylof the called Asubscriber is first reversed by thecalling impulse. After switching in the motor theV signal transmitterprovided for the return Areport performs its first step and releases thecontrol shaft transmitter.

of the main transmitter for its first revolution by, for instance, atripping magnet acting on the blank letter key being energized across acontact controlled by the 'signal control shaft a contact controlled bythis shaft causes the signal transmitter. to advance by a further stepfor the purpose of transmitting the next signal. In this way the signaltransmitter and the control shaft of the main transmitter cooperatealternately by controlling each other alternately.

It is easily possible to combine the return signaling device orindicator with the tele- 0 printer or tele-writer in a self-containedunit and, if desired, to use different switchgear in common. In manycases it is, however. preferable to use the return signaling device as aseparate appliancewhich may be readily 35 connected with standardapparatus .and thus -ing itself from the called up line.

After the revolution of the form a valuable supplement to existingsystems. v

A further considerable simplification may be brought aboutby providingat the exchange station one or a plurality of return signaling devicesfor one group or all the lines combined and by using automaticswitchgcar to effect the connection of a return indicator disengaged atthe time.

After a connection has been made by dispatching series of currentimpulses in a well known manner the return signaling device isautomatically switched in and transmits t'ne return signal, which mayconsist of the name of the town and the name or the numberof the calledsubscriber, to the receiver of the calling subscriber and then againrenders itself automatically inoperative by disconnect- Simultaneouslythe line tothe called subscriber is connected through and is now readyfor transmitting messages. The return signaling device returns to theinitial position of rest only after the two subscribers have beendis'connected.

Thestarting ofthe return signaling ,device in the case of outgoing4tratiic is, however, impossible since the lswitchgear which initiatesthe operation of the naine transmitter is so arranged that it can berendered operative by arriving current impulses only.

. The drawings aiiixed to our speciiication illustrate variousembodiments of our invention.

In the drawings:

Fig. 1 is a return signaling device connected with the distributor ringof an electrically operating tele-writer according to the startstopprinciple,

-F ig. 2 shows a. special construction for a 105 mechanically operatingstart-stop apparatus the contacts of which are controlled by cams ortappets,

Fig. 3 is a detail of the apparatus shown in i110 Fig. 2, and

Figs. 4, 5 and G'illustrate various systems of connection for theapplication of a return signaling device in tele-printer systems withselector operation. In particular various systems of the interlinkingofthe return signaling device with connecting apparatus, such asselectorsof exchanges, are shown in these v figures.

Referring to Fig. 1 of the drawings it will b e seen that a dialselector is utilized as a return signaling device, the arms of which areindicated by the reference letters d1 to da. E is the receiving relaythe armature e of which is reversed as soon as a calling impulsearrives.

This causes the relay X to respond which by 1 means of the contact m1connects in circuit the relay Y. Y now responds and by means of thecontacts fz/1 and y2 connects the source of current S to the apparatusso that its driving motor M starts. Simultaneously the J -relay isenergized in the following circuit: battery, rest contact a, relay J,key A712, selector arm d1, reversed contact ya, battery. The contact lconnects .the stepping magnet D in circuit so that the selector performsits first ste-p.

Simultaneously there is energized the time lag relay V which by meansofthe contacts c. and

'v2 disconnects the keyboard contacts (T) of lthe apparatus. During thestep-by-step mothat the circuit for the relay J remains closed even whena break takes place during the passage of the arm (Z1 from'one contactto the other.

The arms d2 to ZG are now according to the signalto be transmitted;connected .partly to l, partly to `of the battery so that acorresponding series of impulses (for instance -las shown) is sent intothe line when the brush B sweeps across the transmitter disk O.

The brush in known manner, is released, for a complete revolution ateach time,

by the charging current of the condenser C across the contact i3 whenthe J -relay responds.

During the revolution the contact .a is open and is closed only afterthe revolution is completed. In this way the relay J is connected incircuit=anew so that the magnet D is energized again and the selectormakes another step forward. Through the transmitter disk the sequence ofimpulses corresponding with the second selector step, for instance -l-..is now sent into the line. The cycle described is repeated until thedlarm of the selector engages the last contact. I-Iere it stops sincethe contact m3 is -still open.

During the return signaling the time lag relays X, Y and V arepermanently energized. `As soon as theselector has reached the lastcontact the relay V drops open and by the contacts 'v1 and 'v2 whichwere open during the return signaling, connects the keyboard contactsagain to the battery or the network.

The return signaling is now finished and the ordinary traffic maycommence.

During the trafiic the relays X 'and Y con-A tinue to remain energized.traiic is finished the. armature e of thev receiving relay is reversedinto the inoperative position shown. X and Y are then deenergized sothat ac3 is closed again. Through w3 the relay J is made to respond oncemore, D

receives a fresh impulse and advances they selector into the zeroposition. The control magnet St is then no longer'energized because 6@me is already open.

The system is now ready for another call. In the case of outgoingtraffic the switch An, for instance a key, is reversed either prior toor simultaneously with the switching in of the main transmitter. TheY-relay is then tion of the selector the contact is closed soby thecontrol magnet St which is energized Only after the energized across theswitch Anl, so that the contacts y1 and y2 are closed. SimultaneouslyA712 is, however, opened so that the J -relay does not respond and thereturn signaling device does not become operative.

Fig. 2 illustrates va return signaling device operating in a similarmanner in conjunction with a tele-printer the contacts of which arecontrolled by a bank of cams and thus render necessary a specialconnection of the return signaling device.

The first calling impulse arriving over the line Ly energizes thereceiving relay E across the following circuit: line battery (notshown), line a, relay E, closed contact Ico, line b, line battery. Therelay E by closing the switch or contact e causes the relay Y torespond. The relay Y reverses its contacts yl to g4. Through thecontacts y1 and '1 2 the driving motor M is connected to the supply Nand thus the main transmitter started. Through contact ya there isenergized the stepping magnet'D which moves` the signal transmitter,designed as a dial selector, forward by one step. ya is designed as afollower contact and in the attracted stateof ys D would have beendeenergized again if the relay J had not been simultaneously energized fthrough contact .g/i and had not closed the con-l tact z'. The relay Yhas a time lag and remains permanently attracted during the return sig-'naling as well as during the entire trafIic since it cannot be made todrop off by the short interruptions of the contact e.l

When the stepping magnet D is attracted the contact d is closed and thetripping magnet A made to respond. The blank letter key BT,'forinstance', is thusy pulled down l and the control shaft released for onerevolution. cois open so thatl D is deenergized and the contacts cl to765 close in succession. One group of current impulses is then sent intof the line, in correspondence with the combination set up at thecontacts of the dial selector. As soon as the revolution is completedthe contact ko closes so that the relay J -is energized anew and causesthe stepping magnet Dto respond again. The stepping magnet D advancesthe Contact arms Z0-d3 115 by a further step and causes the controlshaft to revolve as before, for instance by operating the blank letterkey BT. In this way the current impulse combination corresponding withthe signs to be returned are sent into the line until the dial selectorhas attained its last step infront of the starting position. In thisposition the contact arm do short circuits the relay J across thecontact f so that i remains open and thel stepping .125 magnet receivesno further current impulses. The return signaling is now finished andthe ordinary traffic can commence.

lVhen the transmission is finished the relay Y is made to drop ofi ifthe line of the During the revolution the contact 105 relay Y ispermanently interrupted since the contact e of the receiving relay Eremains open. The contacts y1 and y2 are opened again and the motorswitched off. The follower contacty3 is closed fora short time so thatthe stepping magnet receives a last impulse and advances its contactarms iO-d5 into the starting position. u

In case of outgoing 4trafiic the switch S is reversed eitherautomatically or by hand.

The relay Y is then energized across Sl and.

thus the driving motor M switched on. The contacts @/3 and g4 whichserve for connecting'up the return signaling device remain, however,inoperative since the relay J is shortcircuited across the contact S2 ofthe reversed switch and the circuit for D was also interrupted by thecontact S3.

Fig. 3 of the drawings illustrates a construction of the contacts k1 toh5. The contact spring 7c is during a certain part of the revolution ofthe control shaft moved into the closed position by a cam n mounted uponthe shaft. This movement can, however, take place then only when thelocking lever hr is located in the release positionlshown in thedrawings. If, for instance, said lever is moved towards the left whenthe transmitter keyboard is operated, it locks the contact and preventsit from moving. The locking levers 7L, lone of Awhich is provided foreach of the contacts c1 to 765, are reversed by keys in deiinitecombinations during ordinary traiic. lVhen the blank letter,key is'depressed, on the other hand, all the levers are in the releaseposition. Since the correct working of the return signaling deviceclemands this position of the levers, t-he blankletter key BT musteither be moved by a release magnet A, as shown in Fig. 2, or thereversal of the locking lever into the release position must be broughtabout by other means, for instance by a special rail, bar or lever whichforces all locking levers back simultaneously and is adapted tobe'operated by a magnet.

Fig. 4 of the drawings illustrates the system-of connection of anexchange for teleprinter systems with dial selector operation inconjunction with a return signaling device by which the name `of thetown and the name of the called up subscriber is adapted to be indicatedat the transmitter station. The transmitter consists of a controllershaft which revolves continuously and a cani shaft which is 'operatedelectro-magnetically. To each transmitter is apportioned a dial selectorwhich sets itself automatically on the line called. The sequence --ofthe current impulses for the individual letters is con- I. trolled by adial selector coordinated to each pre-selector. The number of thetransmitters can be chosen according to the size of the oiice.

It may now be assumed that a calling sub- -After the line selector hasset itself on the i called subscriber the following circuit for theHl-relay and Tl-relay is established in the pre-selector of the calledsubscriber: ground, battery, P3-relay at the line selector, c-arm of theline selector, o-wire, Hl-relay, c-arm of the pre-selector at thecalledfsubscribers station, Tl-relay, ground. i The Tl-relay connectsthe two lines through to the called subscriber with its contacts l .t1and 2 tl. The Rl-relay of the call line linder responds in the followingcircuit: ground, contact 3 h1, contact 4 el, contact 5 @1, winding ofthe Rl-relay, battery, ground. Contact 6 rl closes and establishes acircuit for the stepping magnet D2 of the call finder: ground, delayedaction circuit-breaker LUl, contact 6 r1, contact 7 p1, winding D2 oft'he stepping magnet, battery, ground. The retarded or delayed-actioncircuit breaker LUl energizes the stepping magnet repeatedly until thearm asl of the call finder encounters the dial lselector of the calledsubscriber. The following circuit is then established for the relays Pland El: ground, battery, windings Land Il of the Pl-relay, arm asl ofthe call finder, winding of the El-relay, contact 3M, ground. Thecontact 461 interrupts the circuit for the Rl-relay, the contacts 7191and the contact 61 disconnect the stepping magnet D2 from the time lagcircuit breaker LUl; the contact 8d2 which responds every time thestepping magnet responds prevents a premature de-,energizing of thestepping magnet when the test relay is energized. The contact 9201shortcircuits the high-resistance winding I of the Pl-relayd and thusblocks the call finder against a further engagement.

After the remaining arms as2 to L88 of the call findery have setthemselves on the contacts to which is connected the dial selectorcoordinated tothe called subscriber, in the example illustrated thethird contacts, a circuit is prepared for the stepping magnet D1 throughthe arm or wiper cs2 and the contacts 17 h1 and 12M. The control shaftStWl which revolves continuously, now operates the 'contact 16k by meansof a cam whereby a circuit is completed for the stepping magnet Dl,viz.: ground, contact 16k, wiper as2, contact 17M, wiper dwl, magnetwinding Dl, battery, ground. The dial selector performs one stepandremains on the contact reached next since the control shaft StlVl hasmeanwhile continued its rotation and has broken the contact 16k.

The control shaft then operates the contact 18k by a second cam. Acircuit for the magnet M1 is then established, viz.: ground, battery,winding of the magnet M1, contact 1870, ground. This circuit operates bythe aid of a clutch, not illustrated, the cam shaft los NWlwhichperforms one revolution. The camshaft NlVl closes in succession thecontacts 197s to 257e.l` The contact bank'of the dial selector D1 thecontacts of which are directly connected to the negative or positivepole of a battery is wired in correspondence with the name and the townof the called subscriber. O ne letter consists of 5 different currentimpulses which are sent to the calling subscriber through the wipers0h02 to (i106 of the dial selector D1 standing on the second Contact,the wipers of the call inderllasc to L88 standing on the third contact,contact 24rd and b-wire. The'rst letter consists in the exampleillustrated of thel current impulses: l -l. Apart from this a currentimpulse is sent both at the beginning and at the end of each letter,which impulse passes over the contacts 19k and 2570. After the cam shaftNlVlhas completed one revolution the slowly rotating control shaft StlVlcloses the contact 16k and thus completes the circuit for the steppingmagnet Dl afresh, the magnet Dl performs another step and again remainson the'contact reached after the control shaft has continued itsrotation and opened the contact 167:. The sending of the impulse for thesecond letter takes place in the saine manner as described before.

l/Vhen the last letter has been dispatched the lll-relay responds acrossthe last contact of the dial selector D1 in the following circuit:ground, winding of the lll-relay, Contact lkl, wiper or Contact arm(Z101, winding of the stepping magnet Dl, battery, ground. rlhe steppingmagnet does not respond in this case owing to the high-resistance of thewinding of t-he lll-relay. By means of the contact 241A the call finderis disconnected from the called line and by the contact 25rd the o-lineto the called subscriber is connected through to the called subscriberso that the line becomes free for the transmission of the telegraphingimpulses. Until the next connection is made, the call finder remains inthe position attained; the dial selector Dl is turned back into itsstarting position by interrupting the circuit for the Ul-relay, afterthe calling subscriber has hung up land has thus caused the connectinggear to effect the release. rlhe stepping magnet Dl is made to respondagain through the following circuit: ground, time lag circuit breakerLU2, contact 14M, wiper (Z101, winding of the magnet Dl, battery,ground, and performs a further step 'so that the initial position isattained again.

In the system illustrated in Fig. 5 of the drawings by which town andname of the called subscriber may likewise be given, the transmitterequipment at the exchange station as in Figa) consists of a controlshaft continuously rotated, and a camshaft which is operatedelectromagnetically. The camshaft is, however, designed in such a mannerthat to each letter is apportioned a disk provided with correspondingcams, the disk being able to Connect the positive or the negative poleof a battery to the transmitting de- Vice. To each pre-selector Vl/V isapportioned a dial selector, as in the embodiment described above, thecontrol of which takes place across its own contact arm or wiper whilethe connection to the called line is effected across its second wiper.By a corresponding connection of the individual contacts of the secondbank of contacts of the dial selector to the contacts operated by thecamshaft the correct sequence of letters is obtained for eachsubscriber. s

If a ycalling subscriber has established a connection the H2- andT2-relay in the preselector VW of the called subscriber responds, as inthe arrangement according to Fig. 4 of the drawings. Simultaneously arelay not shown in the drawings is. energized wh-ich closes its contact2151'. By means of a cam, the control shaft Sil/V2 operates contact2067s and completes the following circuit for the stepping magnet D3 ofthe dial selector: ground, contact 20670, contact 2 05t2, wiper (Z107,winding D3 of the stepplng magnet, battery, ground. The magnet moves astep forward and remains stationary on the contact reached since thecontrol shaft has continued its revolution and has again opened thecontact 20670. l

The control shaft then operates the contact 207k by means of a secondcamand comple-tes the following circuit for the magnet M2: ground,battery, winding M2, Contact 207k, ground. lhe magnet M2 throws 1n asuitable clutch and4 thereby causes the camshaft N`W2 to perform arevolution. Across the plus or minus pole, contact 209/0, which isclosed by the cam of the letter wiper (Z108, which in the exampleassumed would stand on the second contact, -line, the series of currentimpulses of the first letter is sent over the wire to the callingsubscriber. rlhe sending of the further letters takes place in the abovedescribed manner after the Contact 206k has been closed again by thecontrol shaft. After the last letter has been dispatched the dialselector performs a further step and remains stationary on the lastcontact since the opened Contact 204712 has interrupted. the circuit tothe time lag circuit breaker LUS. Across the wiper zZ/w8 of the dialselector, the last contact of the dial selector, Contactl 2157', contact213t2, subscriber N2, contact 21422, the line is connected through tothe called subscriber and is thus ready for the transmission of thetelegraphic impulse.

After the completion of the transmission the connecting gear, such aspre-selector, group selector, line selector are tripped in the usualmanner by the calling subscriber hangin conjunction with a relay chain.

ing up his instrument whereby the circuit for the T12-relay in thepre-selector of the called subscriber is broken. The I-I2-relay dropsofi" and connects with its Contact 204712 the time lag breaker LU3 tothe stepping magnet D3 ,which makes another step forward and thusreturns into the starting position.

In Fig. 6 a further modification of the system is illustrated in whichtown and number of the called subscriber is reported back to the caller.The central transmitting equipment consists again of a control shaft anda camshaft, the latter with V11 cams, appor- ,tioned respectively to thename, the town and the figures 0-9. The connection to the called line aswell as the correct sequence of the figures is obtained by a lift rotaryselercltor he number of the lift rotary selectors depends upon thetraiiic which the exchange has to handle, but for each group of 1000subscribers at least one lift rotary selector is necessary. Theselection of an idle lift rotary selector is effected by dial selectorswith preidjustment apportioned specially to each It may now again beassumed that a calling subscriber sends current impulses in the usualmanner across pre-selectors and group selectors for setting the lineselector to a desired subscriber line. In the line selector the A3-relayis thus energized by current impulses. p

The rotary selector with pre-adjustment which in a fairly large exchangemay, for instance, be located in the 7th hundred of the 8th thousandsgroup, is already set to connect with an idle lift rotary selector sinceits turning magnet is permanently energized across earth, battery,winding D4, contact 304253, contact 305t3, locking key SpTl, relay WK3,ground. During each 'response of the stepping magnet the contact 306d4completes a circuit for the relay T3, viz. ground, battery, winding I ofthe T3-relay, Contact 306d4; locking key SpTl, WK3 relay, ground. TheT3-relay interrupts with its contacts 304t3 and 305t3 t@ circuit for thestepping magnet D4 whereby contact 306d4 1s opened and the T3-relaycaused to open again. The contacts 304153 and 305153 close the circuitfor the stepping magnet D4 afresh. The magnet responds and takes a stepforward. This cycle is repeated until the Wiper cia/)15 of the rotaryselector encounters an idle lift rotary selector and completes thefollowing circuit: ground, battery, winding II of the T3-r-elay, lockingkey SpT2, wiper`dw15, Contact 30704, head contact 30870, ground. TheT3-relay is energized and finally arrests the stepping magnet by openingthe contacts 304253 and 30553. By closing the contact 309153 the @-Wireis connected through between the group selector and the line selector.

tery and ground, in order to prevent a response of the stepping magnetD4. This is necessary since in the above circuit the-C3re lay in theline selector also responds and energizes the (E4-relay of the liftrotary selector across the following circuit: ground, winding of the(I4-relay, wiper 51014, contact 31503, contact 316103, resistance W3,battery, ground, which relay opens its contact 30704. The winding II ofthe T3-relay would then become dead and due to the dropping of thecontacts 304zf3 and 305253 complete anew a circuit for the steppingmagnet D4. The relay C3 connects itself with its contact 51103 in thefollowing holding circuit: ground, P4-relay in the group selector, c-armof the group selector, winding III of the 'T3-relay, contact 309133,0-wire, Winding I of the C13-relay, contact 31163, resistance `W2,battery, ground.

By the response of the A3-relay in im-A pulses owing to the currentimpulses sentout by the calling subscriber there is effected the settingof the line selector on the desired subscriber line. If the subscriberline is idle the P5-relay in the line selector is energized and withitso contacts 301195 and 302295 connects through the two connectinglines; by closing the contact 317725 a circuit is prepared for theKl-relay.

By the response of the A3-relay in the line selector the A4-relaycoordinated to the lift rotary selector is likewise energized inimpulses across: ground, contact 303a3, wiper cl'w9, winding of the14A-relay, battery, ground. In this way the lift rotary selector isadjusted in the same manner as the line selector on the contact.corresponding with the number of the called subscriber. The circuit forthe lift magnet of the lift rotary selector is then as follows: ground,battery, winding H3 of the lift magnet, Contact 32611;, contact 325u4,winding of the VS3-relay, contact 319a4, Winding of the relay VVK/l,ground. The V-3 relay being a time lag relay remains energized duringthe sending of impulses and prevents a premature response offthestepping magnet D5 by opening its contact 321v3. After transmission ofthe first series of impulses the V3-relay is shortcircuited by theContact 318a4, it drops o and completes a circuitfor the U4-relay, viz.:ground, winding of the WK4-relay, head contact 32070, which has closedduring the first lift step ofthe lift rotary selector, contact 321/03,contact 32204, winding I of the Uli-relay, Contact 32610, Awinding H3 ofthe lift magnet, battery, ground. The lift magnet does not respond inthis circuit owing to net, battery, ground.

The V3relay again remains energized durlng the transmission of theimpulses and closes a holding circuit for the U4-relay Y across groundContact 328u3, contact 327%4,

Winding II of the Uli-relay, battery, and ground so that the Uli-relayis likewise unable to drop open during the sending of impulses.

After the transmission of the impulses and the testing of the lineselector for an idle subscriber line is linished,a circuit for the relayK1 is prepared by the contact 317375, as already mentioned; the controlshaft StI/V3 Which is continuously rotated closes by the aid of its camy1 this circuit across: ground, contact 353s, Winding I of the Kl-relay,wiper (71013, contact 317 p5, contact 316u3, resistance 73, battery,ground.

. The relay K1 connects itself across ground, contact 351705, Contact342701, Winding II of the Kl-relay, battery, ground in a holding circuitso that it remains energized during the entire duration of the callanswer after it has once responded, like the remaining relays of thechain of relays. rIhe control shaft SV3 now continues to revolve andestablishes by mcans'of a cam af, which closes the contact 352s, thefollowing ci'rcuit for the magnet M3: ground, battery, winding of themagnet M3, contact 352s` and ground. This magnet causes the -camshaftNIV3 to perform a complete revolution by means of a clutchv not shown inthe drawings.

By means of the cam which corresponds with the name of the town of thecalled subscriber and which connects the positive or the name of thetown are thus sent out along the following circuit: positive er negativepole of the battery, contact 358s, contact 331702, contact 329701,contact arm (71011, contact 369u3. contact 302125, b-Wire to thereceiver of the calling subscriber. After the camshaft NW3 has completeda revolution the Cam/2 of the control shaft SWS closes the contact 354sand thus the following circuit for the relay K2: ground, contact 354s,contact 338701, Winding I of the relay K2, battery, and ground. Therelay K2 connects itself across ground, contact 347701, contact 343702,Winding II of the K2-relay, battery, ground, in aholding circuit. Thecontrol shaft StWB, continueslto revolve and again closes by means of afurther cam w the above described circuit for the release magnet M3,

which brings about a second revolution of the camshaft NW3. Let usassume that the subscriber called has the number 8719. Since the liftrotary selector, as assumed is situated in the group of the 8ththousand, the 8th contact bank designating the figure 8 ofthe onecontact set, the contacts of which are connccted With one another, canbe firmly connected t-o the contact 332703. During the second revolutionof the camshaft NW3 the cam coordinated to the figure 8 closes thefollowing circuit for sending out the current impulse corresponding tothisl number, viz.:

positive or negative pole of the battery, contact 329701, contact armdwll, contact 369103, contact 302295, b-Wire to the receiver of thecalling subscriber.

The contact series corresponding to the number 7 cannot be connectedv toadelinite contactl like the thousands number because in this case aspecial lift rotary selector would be necessary for each hundreds group.

This series of contacts is for this reason con` nected by the rotaryselector arm 12 With the respective hundred to which the rotary selectoris coordinated. The contact arm 71016 belongs to a rotary selector, notshown,

Relay K3 connects itself into a holding cir-4 cuit across ground,contact 348702, Contact 344703, Winding II of the relay K3, battery,ground. The cam 00 of the control shaft SLVV3 controls therelease'magnet M3 and again causes a revolution of the camshaft N`W3.The circuit for current impulses corresponding With the number'7 whichthe corresponding cam fof the camshaft NW3 connects to the change-overcontact is as follows :positive or negative pole of the battery, contact333703, co-ntact 330702, contact 329701,

contact arm 71011, Contact 369173, contact 30229-5, ZbWire to thereceiver of the calling subscriber. rI`he issue of the tens and units ofthe number of the called subscriber is obtained by a coordinate-likewiring of the' contacts of the lift rotary selector.

In the contact set designating the tens the contacts are Wired inhorizontal rows, in the second contact set, o n the other hand, whichdesignates the units, in vertical rows. To each of the Wired Contactrows is coordinated a number from 07 to 9 respectively and connected tothe respective change-over contacts 359s to 368s operated by the cams ofthe camshaft NW3.

Since the arms of the lift rotary selector contact 351765.

already stand on the contact corresponding to the number of the calledsubscriber, in the example assumed on the 9th Contact of the irstdecade, the following circuit is established for the issueof the tensnumber after the control shaft StV3 has energized by its cams y 4 andthe relay K4 and the release magnet M3, respectively, viz.: positive ornegative pole of the battery, change-over contact 368s, vertical row ofcontacts 1, horizontal row of cont-acts 1, contact 9, contact arm g1ofthe lift rotary selector, contact 336705, Contact 3357u4, contact333763, contact 33072, contact 329761, contact arm (71011, contact369u3, contact 302125, h-wire, to the receiver of the callingsubscriber. For the release of the unit number, after the control shaftStlV3 has again energized the relay K5 and the magnet M3 by the cams ?/5and respectively, the circuit is as follows: positive or negative poleof the battery, contacts 360s, vertical row of contacts 9, contact armg2 of the litt rotary selector, contact 337765, contact 335704, contact33373, contact 3307c2,con

tact 329701, contact arm d'w11, contact 369103,.

contact 302225, 7 wire t0 the receiiger of the calling subscriber. Thiscompletes the call return or answering of the name of the town and thenumber ot the called subscriber.

When the relay K5 responds the holding circuit for the relay -Kl isbroken by the The relay K1 drops off with time lag so that the lastligure is still issued with certainty. By the release of the relay K1there is initiated the stepwise drop of the relay chain K1 to K5 by thecontact 342761 opening the holding circuit for the relay K1; relay K1drops ott and opens through contact 347701 the'holding circuit for therelay K2, the latter drops oit and opens the holding circuit for relayK3 and so on until relay K5 drops oil and the chain of relays is thusdeenergized again. When the relay K5 re- -sponds the relay K1, being atime lag relay, does not drop otf at once; in this way the followingcircuit is completed for the relay U3 in the line selector LW: ground,Contact 371765, contact 370761, Contact arm (Z1010,- winding I of ctherelay U3, head contact 3137s, resistance 72, battery, ground. The relayU 3 responds and on the one hand switches the b-line through to thecalled subscriber by closing its contact 373u3 and on the other handdisconnects the rotary selector from the connecting line. The line isnow ready forthe transmission of the telegraphic impulses. For the relayU3 the following holding circuit is completed: ground, winding 1I of therelay U3, contact B14/a3, head contact 31370, resistance W2, battery,and ground. The contact 316173 has opened the circuit of the relay C4,relay C4 drops open and closes the contact 307 c4. The stepping magnetD5 of the lift rotary selector is again energized by the dropping of thecontact 32304 along the following circuit: l

ground, winding of the relay WK4, head contact '32070, contact 321/03,Contact 32304,

contact 374%, winding D5 of the steppingn4 magnetLbattery, and ground.

The contact 37 3675 is closed in consequence of the attraction of thestepping magnet D5 and establishes a circuit for the relay U4, viz.:ground, Contact 373675, winding Il of the U4-relay, battery, ground.Contact 374274 then opens againfand interrupts the circuit for thestepping magnet. rlhe stepping magnet D drops ott and interrupts thecircuit for the relay U4, whereupon the said -magnet D5 is againenergized across the ing telegraph transmitting and receiving`mechanisms at each of the stations, a central oiice, means at saidotlice for establishing connections between said subscribers stations asdesired, and automatic means operating on extending a connection to adesired station for sending back to the calling station signals whichcharacterizel the desired sta-- tion, said automatic means beingarranged to operate said receiving mechanism at the calling station.

2. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central otlice, means at said otlice forestablishing connections between said subscribers stations as desired,and automatic means operating on extending a connection to a desiredstation for sending back to the calling station signals whichcharacterize the desired station, said automatic means consisting of astepping mechanism adapted to produce groups of impulses for operatingsaid receiving mechanism at the calling station.

3. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting `and receiving mechanisms ateach of the sta-tions, a central oiice, means at said office forestablishing connections between said subscribers stations as desired,and automatic means operating on extending a connection to a desiredstation for sending back to the calling station groups of impulses whichcharacterize the desired station, said automatic means consisting of aselector-,like stepping switch whose bank conimpulses.

4. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oiiice, means at said oicefor-establishing connections between said subscribers stations asdesired, and automatic means which upon the extension of a connection toa desired station will produce groups of impulses characterizing thedesired station for operating said receiving mechanism at the callingstation, said automatic means'comprislng a se- Jlector-like steppingswitch whose contact bank is wired according to said groups of im`pulses, and a printing telegraph transmitting mechanism whose contactsare connected with' the wipers of said stepping switch.

5. In a printing telegraph exchange sys.-

tem, a plurality of subscribers stations, printing telegraphtransmitting and receiving mechanisms at each of the stations, a centraloffice, means at said oiiice for establishing connections between saidsubscribers stations as desired, and automatic means which upon theextension of a connection to a desired station will produce groups ofimpulses characterizing the desired station for operating said receivingmechanism at the calling station, said automatic means comprising aselector-like stepping switch whose contact bank is wired according tosaid groups of impulses, and a printing telegraph transmitting mechanismwhose contacts are connected in series with the corresponding wipers ofsaid stepping switch.

6. In a vprinting telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oiiice, means at/said office forestablishing con- ,y nections between said subscribers stations asffp/ldesired, and automatic means comprising a stepping mechanism. land aprintingy telegraph transmitting( chanism whose contacts are connected'wv ylteach other, which mea-ns, upon the extension'of a connection to adesired station, will produce grqups of impulses characterizing thedesired station for operating said receiving mechanism at the callingstation, the stepping-on of said stepping mechanism and the rotation ofsaid transmitting mechanism being dependent upon each other.

7. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oiiiee, means at said olice forestablishing connections between said subscribers stations as desired,and automatic means comprising a stepping mechanism and a printingtelegraph transmitting mchanism whose contacts are connected with eachother, to prothe stepping-on of said stepping mechanisml being effectedby a contact which is controlled by said transmitting mechanism.

8 In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph'transmitting and receiving mechanisms ateach of the stations, a central office, means at said oiice forestablishing connections between said subscribers stations as desired,and automatic means comprising a stepping 'mechanism andl a printingtelegraph transmitting mechanism whose contacts are connected with eachother, to produce, upon the extension of a connection to a desiredstation, groups of impulses `characterizing the desired station foroperating said receiving mechanism at the calling station, saidtransmitting mechanism consisting ofV a plurality of contacts and acommon cam spindle controlling them..

9. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oiice, means at said office forestablishing connections between said subscribers stations as desired,and automatic means comprising a stepping mechanism and a printingtelegraph transmitting mechanism whose contacts are connected with eachother, to produce, upon the extension of a connection to a desiredstation, groups of impulses characterizing the desired station foroperating said receiving mechanism at the calling station, contacts, acommon cam spindle controlling said contacts, and a continuouslyrevolving control '),/',l/,Q y,In a' printing telegraph exchangesystenta/f` la plurality of subscribers stations, printing telegraphtransmitting and receiving mechanisms at each of the stations, a centraloflice, means at said oiiice'for establishing connections between saidsubscribers stations as desired, and automatic means which, upon theextension of a connection to a desired station, will produce groups ofimpulses characterizing the desired station for operatingl saidreceiving mechanism at the calling station, the operation of saidautomatic means being effected when engaging the desired station.

11. In a printing telegraph exchange system, a plurality of subscribers"stations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central o iiice, means at said oiiice forestablishing connections between said subscribers stations as desired,and automatic 'means which, upon the extension of a connection to adesired station, will pro'duce groups of impulses characterizing thedesired station for operating said receiving mechanism at the callingstation, the operationof Vsaid automatic means being effected by meansof a relay becoming operative when engaging the desired station. e 12.In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oice, means at said ollice forestablishing connections between said subscribers sta- 4 tions asdesired,and automatic means which,

upon the extension of a connection to a desired station, will producegroups of impulses characterizing the desired station for operating saidreceiving mechanism at the calling station, said automatic meansbeingarranged at said central oliice.

13. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiv- 1 ing mechanismsat ,each of the stations, a

central olice, means at said olce for establishing connections betweensaid subscribers stations as desired, and automatic means which, uponthe extension of a connection to a desired station, will produce groupsof impulses characterizing the desired station for operating saidreceiving mechanism' at the calling station, said automatic means beingarranged at said central olice and assigned to a plurality ofsubscribers stations.

14. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oice, means at said oiice forestablishing connections `between said subscribers stations as desired,automatic means at said office for producing, upon the extension of a-connection to a desired station, groups of impulses characterizing thedesired station to operate said receiving mechanism at the callingstation, and automatic contact devices for cutting through saidconnection to the desired station after the answer back is inished.

15. In a printing telegraph exchange system, a plurality of. subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central office, means at said office forestablishing connections between said subscribers stations as desired, aplurality of automatic devices at said oliice for producing, upon theextension of a connection toa desired station, groups of impulsescharacterizing the desired station to operate said receiving mechanismat the calling station, and yselector switches for automaticallylswitching onto said connection an idle one of said automatic devices.

16. In a printing telegraph exchange system, a plurality of subscribersstations,

' printing telegraph transmitting and receivthe operation of saidselector switches being effected by a relay becoming operative whenengaging the desired subscribers line.

17. In a printing telegraph exchange system, a plurality of subscribersstations, printing telegraph transmitting and receiving mechanisms ateach of the stations, a central oiiice, means at said office forestablishing connections between said subscribers stations as desired,and automatic means at said oiiice for producing, upon the extension ofa connection to a desired station, groups of impulses characterizing thedesired station to operate said receiving mechanism at the callingstation, said automatic means comprising a plurality of steppingswitches each of which is assigned to, and has its contact wiredinaccordance with, one of the subscribers stations, a plurality oftransmitting mechanisms adapted to generate groups of impulses foroperating the printing telegraph receiving mechanisms at the subscribersstations, and a plurality of selector switches each of which upon theextension of said desired connection, automatically connects an idle oneof said transmitting mechanisms with that of said stepping switcheswhich is assigned to the desired station.

18. In a printing telegraph system, a plurality of subscribers stations,printing telegraph transmitting and receiving mechanisms at each of thestations, a central office for establishing connections between L. saidsubscribers stations as desired, and automatic transmitting meansoperating on extending a connection to a desired station for sending outto a calling subscribers station a predetermined series of impulsecombinations characterizing a called station, said automatictransmitting means consisting of signal producing means representinyen aseries of impulse combinations in a fixed fo m, and of'distributingmeans for sending. out said impulse combinations in identical mannercorretures.

AUGUST JIPP. t EHRHARD ROSSBERG. FRANZ SIMON. ALFRED SCHEUNERT. WILLYSKAWRAN.

